Question

A 1000.kg car moving at north at 100. km/hr brakes to a stop in 50. m within a uniform acceleration. what are magnitude and direction of the net force on the car ?

thank you so much

Answer 1

Force=7.71KN in the opposite direction

Step-by-step explanation:

Given the mass of the car(M)=1000Kg

The initial speed of the car(u)=100km/hr

we know that 1km/hr=5/18 m/sec

100km/hr=100*5/18 m/sec=27.77m/sec

the distance travelled before it stops (s)=50m

let the acceleration of the car be a

The final velocity of the car is 0.

we know that
`v^(2)-u^(2)=2as`

`0^(2)-27.77^(2)=2(-a)(50)`

a=7.712m/
`sec^(2)`

We know that F=Ma

F=1000* 7.712=7712N=7.71KN